z=x+yi(x,y∈R)的平方等于5+12i,求复数z
z=x+yi(x,y∈R)的平方等于5+12i,求复数z 答案z=3+2i或z=-3-2i 求详细过程
(x+yi)^2=x^2-y^2+2xyi=5+12i, 由复数相等的条件得 x^2-y^2=5,① 2xy=12,② ①*6-②*5/2,6x^2-5xy-6y^2=0, ∴x=3y/2,或x=-2y/3. 分别代入②,得y^2=4,或y^2=-9(无实根), ∴y1=2,y2=-2; 对应的x1=3,x2=-3.
答:复数z=x+yi(x,y∈R),满足│z│=1, 设x=cosa,y=sina │z-1-i│ =│x+yi-1-i│ =│(x-1)+(y-1)i│ =│(c...详情>>